CVE-2026-40321: CWE-87: Improper Neutralization of Alternate XSS Syntax in dnnsoftware Dnn.Platform
DNN (formerly DotNetNuke) is an open-source web content management platform (CMS) in the Microsoft ecosystem. Prior to version 10.2.2, a user could upload a specially crafted SVG file that could include scripts that can target both authenticated and unauthenticated DNN users. The impact is increased if the scripts are run by a power user. Version 10.2.2 patches the issue.
AI Analysis
Technical Summary
CVE-2026-40321 is an improper neutralization of alternate XSS syntax vulnerability (CWE-87) in DNN Platform before version 10.2.2. It allows an attacker to upload a crafted SVG file containing malicious scripts that can execute in the context of the application, potentially affecting both authenticated and unauthenticated users. The vulnerability is mitigated by the official patch in version 10.2.2.
Potential Impact
Successful exploitation can lead to high impact including confidentiality, integrity, and availability compromise due to script execution in users' browsers. The risk is elevated when scripts run with power user privileges, potentially enabling broader control or data exposure within the affected DNN installation.
Mitigation Recommendations
Upgrade DNN Platform to version 10.2.2 or later, which includes the official fix for this vulnerability. Patch status is not explicitly stated in the vendor advisory, but the version update indicates remediation. No additional mitigations are specified.
CVE-2026-40321: CWE-87: Improper Neutralization of Alternate XSS Syntax in dnnsoftware Dnn.Platform
Description
DNN (formerly DotNetNuke) is an open-source web content management platform (CMS) in the Microsoft ecosystem. Prior to version 10.2.2, a user could upload a specially crafted SVG file that could include scripts that can target both authenticated and unauthenticated DNN users. The impact is increased if the scripts are run by a power user. Version 10.2.2 patches the issue.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-40321 is an improper neutralization of alternate XSS syntax vulnerability (CWE-87) in DNN Platform before version 10.2.2. It allows an attacker to upload a crafted SVG file containing malicious scripts that can execute in the context of the application, potentially affecting both authenticated and unauthenticated users. The vulnerability is mitigated by the official patch in version 10.2.2.
Potential Impact
Successful exploitation can lead to high impact including confidentiality, integrity, and availability compromise due to script execution in users' browsers. The risk is elevated when scripts run with power user privileges, potentially enabling broader control or data exposure within the affected DNN installation.
Mitigation Recommendations
Upgrade DNN Platform to version 10.2.2 or later, which includes the official fix for this vulnerability. Patch status is not explicitly stated in the vendor advisory, but the version update indicates remediation. No additional mitigations are specified.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-10T21:41:54.505Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69e2a83ebdfbbecc5994f140
Added to database: 4/17/2026, 9:38:06 PM
Last enriched: 4/17/2026, 9:53:11 PM
Last updated: 4/21/2026, 12:17:54 AM
Views: 23
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